This disclosure relates to medical fluid delivery sets and related systems and methods. In some aspects of the invention, a medical fluid delivery set includes a syringe connected to a series of interconnected fluid lines. The syringe includes a medical fluid containment cylinder and a plunger assembly that can be axially moved relative to the medical fluid containment cylinder. The plunger assembly includes an inner plunger shaft including a seal that is slidably disposed within the medical fluid containment cylinder and an outer plunger shaft that at least partially surrounds the inner plunger shaft to form a space between an outer surface of the inner plunger shaft and an inner surface of the outer plunger shaft that is sized to receive a wall of the medical fluid containment cylinder therein.
